FAQ

Real questions only. Anything asked twice in the wild gets added. Nothing here is invented as a way of writing marketing copy in question form.

Because the project is new, this page is short, and most of what is here is questions asked during the design rather than by builders. It will get longer and more useful as people build things.

Can I buy one?

Not yet. Kits are intended eventually, and nothing has been fabricated, so there is nothing to sell.

Can it deploy my parachute?

No, and it never will.

oApogee is a passive instrumentation payload. It does not fire ejection charges, control deployment, ignite motors, or command any pyrotechnic device. Your recovery system is the motor's ejection charge and delay grain, exactly as it was before you fitted a payload.

This is a design boundary rather than a missing feature. Deployment control carries a completely different set of failure consequences and belongs to certified high power rocketry.

Why is there no price on the bill of materials?

Because nothing has been bought, so there is no honest number to put there.

This site does not publish figures it has not measured or sourced. The targets in the project brief are under $60 for the full build and under $30 for the entry build, but a target is not a measurement, and printing one as though it were is how a site becomes untrustworthy.

Do I need to know how to program?

No. The microcontroller is flashed by dragging a file onto what appears as a USB drive. There is no toolchain to install.

You do need to have soldered before, and to be able to use a multimeter for continuity and voltage.

Do I need a radio licence?

Not for the default configuration. oApogee Link and Track use the 902 to 928 MHz band in the US under FCC Part 15, which requires no licence and no callsign.

oApogee Solo has no transmitter at all, which is one of the reasons it exists.

If you hold an amateur licence there is a separate path with more transmit power available, covered on the safety page. Those two regimes are different and the site never mixes them.

Can I fly it outside the US?

The band changes and so do the rules. A 902 to 928 MHz module is not legal to operate in most of Europe, where the equivalent short range band is 863 to 870 MHz, and that is a different radio module rather than a firmware setting.

The EU and UK rules are not yet documented properly on this site, including whether airborne use is permitted, which several national administrations restrict. That is marked as unfinished rather than guessed at. See the safety page.

Will it fit my rocket?

The internal sled fits a 24 mm coupler or a BT-50 payload bay. The external pod straps to the outside of any body tube and requires no modification to the airframe, which is what makes it work on a rocket you already own.

The pod costs you drag and moves your centre of gravity, so re-simulate before flying. That is not a formality.

What is the highest it can go?

Unverifiedtwo separate ceilings, and readers will conflate them. The barometer has a usable pressure range that corresponds to some altitude, and the radio has a practical range that is usually the lower limit in practice. Both need stating with their conditions.

The design target is low power flying, A through E motors, with headroom so that F and G are not blocked later.

Why not a microSD card?

Because card sockets unseat under boost.

A microSD card is held in by a friction detent, and the acceleration on even a modest motor is enough to move it. In DIY flight computers this is the single most common in-flight failure, and its failure mode is the worst available: the flight proceeds normally and the data is simply gone.

The flash on oApogee is soldered down and cannot unseat. The cost is that you offload over USB instead of moving a card, which is a mild inconvenience on the ground in exchange for removing a failure mode in the air.

Why does my altitude read slightly negative after landing?

That is usually correct rather than a fault.

Altitude is measured against a pressure reference taken on the pad. If atmospheric pressure rose during the flight, or the rocket landed lower than the pad, the reading goes negative. oApogee does not clamp it at zero, because clamping would hide a real measurement.

See my altitude reads negative for the cases where it does indicate a problem.

What does the o stand for?

Open. That is the whole story, and it is told once, on the about page.

How do you pronounce it?

"oh-APP-uh-jee."

Is this related to Apogee Components?

No. oApogee is not affiliated with Apogee Components, who are an unrelated and much older retailer in this hobby. The name is never shortened to "Apogee" for exactly that reason.

Can I help?

Yes, and the most useful help right now is telling us where the site is wrong.

The safety and regulatory pages especially. They are written carefully and have not been reviewed by anyone with formal expertise in the rules they describe.